UI Improvements (#219)

- use react-resizable-panels for UI
- improve icons for buttons
- improve mobile layout with drag/resize panels

ui/package.json

@@ -14,6 +14,8 @@
     "@tanstack/react-query": "^5.80.6",
     "react": "^19.1.0",
     "react-dom": "^19.1.0",
+    "react-icons": "^5.5.0",
+    "react-resizable-panels": "^3.0.4",
     "react-router-dom": "^7.6.2",
     "tailwindcss": "^4.1.8"
   },
@@ -30,4 +32,4 @@
     "typescript-eslint": "^8.30.1",
     "vite": "^6.3.5"
   }
-}
+}